The field of biomaterials has been an area of intensive research for decades. Biocompatibility of synthetic materials with biological tissue has been a major goal of developing synthetic materials to solve medical problems and facilitate the repair mechanisms of living organisms (specifically animal/human). Often synthetic materials are rejected by the in-vivo application of such materials. The complex aspects of compatibility of synthetic and biological systems are not well-recognized and the search for biocompatible systems has often centered on the chemical structure of synthetic materials. In the area of blood compatibility, for example, heparin-like surfaces have been intensively studied with synthetic polyelectrolyte complexes being an area of promising results but not effective enough for practical utility. Other studies have concluded that reduced surface free energy is desired and indeed surfaces such as silicone rubber and PTFE (e.g., Teflon® fluoropolymers), show improved blood compatibility over higher surface energy polymers but far from acceptable results. One approach has been to provide scaffolds for cell growth for coating synthetic polymers to provide compatibility (e.g. blood compatibility). One of the earliest references to this approach involved the utilization of a non-woven polypropylene microfiber web attached to a synthetic substrate (e.g. thermoplastic polyurethane) with Parylene C deposited by vacuum deposition/polymerization (Byck, J. S., Chow, S., Gonsior, L. J., Miller, W. A., Mulvaney, W. P., Robeson, L. M. and Spivack, M. A., in Polymeric Materials for Circulatory Assist Devices; Artificial Heart Program Conference Proceedings, Hegyeli, R. J. (Ed) (1969) U.S. Printing Office, Washington, D.C., p. 123). The microfiber web allowed for the endothelial cell adhesion and growth providing the blood compatibility to artificial heart surfaces. Although some success was achieved, this approach was not deemed practical due to severe material requirements and time/effort involved with cell growth. Other biomaterials such as wound coverings, stents, bone reconstruction, hip replacement, heart valves also require biocompatibility. Each system may require unique approaches towards achieving the desired biocompatibility. While the emphasis in biomaterials research has been placed on the chemical structure of the synthetic materials, the recognition that the surface morphology may play a key role is a recent development. A number of approaches have been proposed and experimental research has been reported showing promising trends/results relative to nano-structured surfaces. These approaches include phase separated blends and carbon nanotube surfaces.
A biomimetic/nanotechnology analysis has well-demonstrated the unique properties observed in nature for specific nanostructured surfaces. Synthetic approaches offering analogous surfaces have also demonstrated the unique surfaces. The synthetic approaches reported, however, are not viable/economic methods for achieving such systems for large scale utility. Methods/processes are needed to transform the biomimetic/nanotechnology observations into practical approaches for achieving obtaining biomedical materials. There is a need in this art for a method capable of replicating these features or surfaces at nano-scale dimensions that is scaleable to provide relatively large areas with these features. There is also a need in this art for a process that produces continuous nano-structured surfaces using a wide range of polymers. The instant invention discloses a methodology that can translate the biomimetic/nanotechnology concepts into viable/economic approaches to utilize the unique characteristics inspired by nature.